Liquid crystal device  and electronic apparatus

ABSTRACT

A liquid crystal device is provided which includes: a first substrate and a second substrate that are disposed to face each other; a liquid crystal layer that is sandwiched between the first substrate and the second substrate; a first electrode that is provided on the liquid crystal layer side of the first substrate; an insulating layer that is provided on the liquid crystal layer side of the first electrode; and a second electrode that is provided on the liquid crystal layer side of the insulating layer, in which the first substrate has formed thereon a plurality of data lines and a plurality of scan lines which intersect each other; sub-pixels are formed at regions surrounded by the data lines and the scan lines; the second electrode has a plurality of linear electrodes that is disposed with a gap therebetween; each of the plurality of linear electrodes extends in a long-axis direction of the sub-pixels and has at least one bent portion; the bent portion has such a shape that both sides thereof are inclined in opposite directions with respect to the long-axis direction of the sub-pixels; and the data lines or the scan lines are bent in an extending direction of the linear electrodes having the bent portion.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 12/397,408 filed Mar. 4, 2009, which applicationclaims priority to Japanese Patent Application No. 2009-009615 filed inthe Japanese Patent Office on Jan. 20, 2009, and Japanese PatentApplication No. 2008-055867 filed in the Japanese Patent Office on Mar.6, 2008, the entire contents of which are incorporated herein byreference.

BACKGROUND

1. Technical Field

The invention relates to a liquid crystal device and an electronicapparatus.

2. Related Art

Hitherto, as one means for achieving a wide viewing angle of an liquidcrystal device, there has been used a mode in which an electric field isapplied to a liquid crystal layer in a direction of a substrate plane tothereby control alignment of liquid crystal molecules (such a mode willbe referred to as a lateral electric field mode), and an IPS (In-PlaneSwitching) mode and an FFS (Fringe-Field Switching) mode have been knownas such a lateral electric field mode. In a lateral electric field modeliquid crystal device, a pixel electrode and a common electrode aretypically formed on the same substrate. In the case of the IPS mode, thepixel electrode and the common electrode are formed on the same layerand have a comb-teeth shape. On the other hand, in the case of the FFSmode, the pixel electrode and the common electrode are formed ondifferent layers, respectively, and one of them has a comb-teeth shapeand the other has a beta shape. In particular, in the case of the FFSmode, since the pixel electrode and the common electrode are formed ondifferent layers, a strong electric field is generated from a fringeportion of the electrode in a direction inclined with respect to thesubstrate plane. Therefore, the FFS mode has a merit that the alignmentof liquid crystal molecules disposed right above the electrode can beeasily controlled compared with the IPS mode.

As a method for achieving a further wider viewing angle with the lateralelectric field mode liquid crystal device, there is a known method thatforms a plurality of regions, a so-called multi-domain, in which liquidcrystal molecules within one sub-pixel are aligned in differentdirections upon voltage application (a region where liquid crystalmolecules are aligned in approximately one direction is referred to as adomain). Since the viewing angle characteristics corresponding toinherent contrast ratios of respective domains are compensated byforming multiple domains, it is possible to achieve a wide viewingangle. In order to form a multi-domain structure, the shape of acomb-teeth shaped electrode needs to be studied. When electrode fingersconstituting a comb-teeth shaped electrode are referred to as “linearelectrodes,” rather than arranging the entire linear electrodes withinone sub-pixel to extend in the same direction, for example, asillustrated in FIG. 11, linear electrodes 101 a corresponding an upperhalf part of one sub-pixel are arranged to be inclined toward the topleft corner in FIG. 11 and linear electrodes 101 b corresponding to alower half part thereof are arranged to be inclined toward the bottomleft corner. A electric field is generated in a direction perpendicularto the extending direction of the linear electrodes 101 a and 101 b uponapplication of an electric voltage. Liquid crystal molecules are causedto be aligned in accordance with the electric field. In the case of FIG.11, two regions (the upper half part and the lower half part of thesub-pixel) where liquid crystal molecules are aligned in differentdirections are generated, whereby a dual-domain structure is achieved.

Here, since a uniform lateral electric field is generated in portions(encircled region indicated by symbol A in FIG. 11) of an liquid crystallayer disposed in the vicinity of the center portions of the linearelectrodes 101 a and 101 b, images can be properly displayed. However,since lateral electric fields are generated in various directions inportions (encircled regions indicated by symbol B in FIG. 11) of thelinear electrodes 101 a and 101 b disposed in the vicinity of endportions thereof, the alignment of the liquid crystals is disordered,and thus, light transmittance during bright display is remarkablydeteriorated at these locations. Therefore, in this configuration, thearea capable of substantially contributing to display is decreased, andthus, it is difficult to obtain a sufficient aperture ratio of the pixeland to achieve a high display luminance. In this respect, there isproposed a multi-domain liquid crystal display device in which in lieuof the configuration of FIG. 11 where the linear electrodes are arrangedto extend in a short-axis direction of the sub-pixel, the linearelectrodes are arranged to extend in the long-axis direction of thesub-pixel (see Japanese Unexamined Patent Application Publication No.2002-014374). Specifically, the pixel electrode and the common electrodeare arranged to extend in the long-axis direction of the sub-pixel sothat they are bent several times.

According to the configuration disclosed in Japanese Unexamined PatentApplication Publication No. 2002-014374, since the area of the endportions of the linear electrodes within one sub-pixel is small comparedwith the configuration illustrated in FIG. 11, it is possible toincrease the area, which is able to substantially contribute to display,to thereby increase the aperture ratio of the pixel. However, since thepixel electrode and the common electrode are bent with respect to thesub-pixel having an approximately rectangular shape, there is generateda triangular dead space which does not contribute to display along thedata line (the longer side of the sub-pixel), and thus, the apertureratio is decreased in this portion. Consequently, there is a problemthat it is difficult to achieve a high display luminance.

SUMMARY

An advantage of some aspects of the invention is that it provides aliquid crystal device having a high pixel aperture ratio, a high displayluminance and a wide viewing angle and an electronic apparatus using theliquid crystal device.

According to an aspect of the invention, there is provided a liquidcrystal device including a first substrate and a second substrate thatare disposed to face each other; a liquid crystal layer that issandwiched between the first substrate and the second substrate; a firstelectrode that is provided on the liquid crystal layer side of the firstsubstrate; an insulating layer that is provided on the liquid crystallayer side of the first electrode; and a second electrode that isprovided on the liquid crystal layer side of the insulating layer, inwhich the first substrate has formed thereon a plurality of data linesand a plurality of scan lines which intersect each other; sub-pixels areformed at regions surrounded by the data lines and the scan lines; thesecond electrode has a plurality of linear electrodes that is disposedwith a gap therebetween; each of the plurality of linear electrodesextends in a long-axis direction of the sub-pixels and has at least onebent portion; the bent portion has such a shape that both sides thereofare inclined in opposite directions with respect to the long-axisdirection of the sub-pixels; and the data lines or the scan lines arebent in an extending direction of the linear electrodes having the bentportion. Here, “sub-pixel” in the invention is a region which serves asthe minimum unit of displaying an image. Moreover, the sub-pixels areprovided so as to correspond to colored layers having different colorsof color filters, and one pixel is formed by a plurality of adjacentsub-pixels.

According to the liquid crystal device of the above aspect of theinvention, since each of the linear electrodes constituting the secondelectrode is generally arranged to extend in the long-axis direction ofthe sub-pixels and includes at least one bent portion, and the bentportion has such a shape that both sides thereof are inclined inopposite directions with respect to the long-axis direction of thesub-pixels, a multi-domain structure is formed, and thus, it is possibleto achieve a wide viewing angle. Moreover, since the data line is bentin the extending direction of the linear electrodes having the bentportion, it is possible to suppress dead spaces which do not contributeto display from generating along the longer sides of the sub-pixel, andthus, a high aperture ratio can be maintained.

In the above aspect of the invention, the first electrode may be a pixelelectrode and the second electrode may be a common electrode.

According to such a configuration, since the insulating layer is formedon the pixel electrode and the common electrode having a plurality oflinear electrodes is formed on the surface of the insulating layer so asto cover the entire sub-pixels, it is possible to maximize the apertureratio of the sub-pixels.

In the aspect of the invention, each of the plurality of linearelectrodes may be linearly symmetric about a short-axis direction of thebent portion.

In the aspect of the invention, a region disposed between bent portionsof two linear electrodes adjacent in a short-axis direction of thesub-pixels may be a gap between the two adjacent linear electrodes.

The configuration can be restated as follows: when the gap between twoadjacent linear electrodes is referred to as a “slit,” since the slit isformed between bent portions of the two adjacent linear electrodes, theconfiguration means that the slits are connected with each other acrossboth sides of the bent portions in the long-axis direction of thesub-pixels. According to such a configuration, it is possible tomaximize the aperture ratio of the sub-pixels.

Alternatively, a connection portion may be provided to a region disposedbetween bent portions of two adjacent linear electrodes in a short-axisdirection of the sub-pixels so as to connect the two adjacent linearelectrodes with each other.

The configuration can be restated as follows: the configuration meansthat the slits on both sides of the bent portions in the long-axisdirection of the sub-pixels are divided by the connection portion. Whenthe slits are connected with each other across both sides of the bentportions, there is a fear that it may cause problems that displaydefects resulting from an alignment disorder (disclination) of liquidcrystals at the bent portions may spread or that the display defects maybe unstably transferred to other positions upon application of anexternal force to the liquid crystal device. However, it is possible tosolve the problems by dividing the slits on both sides of the bentportions by the connection portion.

In the above aspect of the invention, among the linear electrodes andthe gaps alternately arranged in a short-axis direction of thesub-pixels, the linear electrode and the gap disposed at a regionlocated close to the bent data line (or the bent scan line) may have awidth larger than a width of the linear electrode and the gap disposedat a region located distant from the bent data line (or the bent scanline).

Alternatively, among the plurality of linear electrodes arranged in ashort-axis direction of the sub-pixels, the linear electrode disposed ata region located close to the bent data line (or the bent scan line) mayhave a width larger than a width of the linear electrode disposed at aregion located distant from the bent data line (or the bent scan line).

Alternatively, among a plurality of the gaps arranged in a short-axisdirection of the sub-pixels, the gap disposed at a region located closeto the bent data line (or the bent scan line) may have a width largerthan a width of the gap disposed at a region located distant from thebent data line (or the bent scan line).

According to the configuration of the above aspect of the invention,although it is possible to provide a high aperture ratio, there is afear that when a larger part of the outer border of the second electrodeis located in close proximity of the data line, due to the influence ofan electric field generated between the data line and the secondelectrode, the alignment of the liquid crystal molecules between them isdisordered, thus leading to display defects. Therefore, when the widthof at least one of the linear electrode and the gap disposed at a regionlocated in the vicinity of the circumference of the sub-pixel and closeto the data line is larger than the width of at least one of the linearelectrode and the gap disposed at a region located in the vicinity ofthe center of the sub-pixel and distant from the data line, it ispossible to make the second electrode less likely to be influenced bythe data line to thereby suppress the alignment disorder of the liquidcrystal molecules between them.

The liquid crystal device according to the above aspect may furtherinclude a light shielding film configured to overlap with the data line(or the scan line) which is at least bent in plan view, the lightshielding film being provided on the first substrate.

According to such a configuration, since the data line and the lightshielding film are formed on the first substrate, it is possible toperform the positional alignment between the data line and the lightshielding film with a high accuracy compared with the case where thedata line and the light shielding film are formed on differentsubstrates. Accordingly, it is possible to achieve a high apertureratio.

Further, the liquid crystal device may further include a light shieldingfilm configured to overlap with the data line (or the scan line) whichis at least bent in plan view, the light shielding film being providedon the second substrate.

According to another aspect of the invention, there is provided anelectronic apparatus having the liquid crystal device according to theabove aspect of the invention. According to such a configuration, it ispossible to realize an electronic apparatus having a liquid crystaldisplay unit capable of achieving a high display luminance and a wideviewing angle.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an equivalent circuit diagram of an liquid crystal deviceaccording to a first embodiment of the invention.

FIG. 2 is a plan view illustrating a configuration of one pixel of theliquid crystal device according to the first embodiment.

FIG. 3 is a cross-sectional view illustrating the configuration of onepixel of the liquid crystal device according to the first embodiment.

FIG. 4 is a plan view illustrating a configuration of one pixel of aliquid crystal device according to a second embodiment of the invention.

FIG. 5 is a plan view illustrating a configuration of one pixel of aliquid crystal device according to a third embodiment of the invention.

FIG. 6 is a plan view illustrating a configuration of one pixel of aliquid crystal device according to a fourth embodiment of the invention.

FIG. 7 is a cross-sectional view illustrating the configuration of onepixel of the liquid crystal device according to the fourth embodiment.

FIG. 8 is a diagram illustrating an arrangement of optical axes of theliquid crystal device according to the fourth embodiment.

FIG. 9 is a cross-sectional view of a liquid crystal device according toa modification.

FIG. 10 is a perspective view illustrating an example of an electronicapparatus according to the invention.

FIG. 11 is a plan view illustrating an example configuration of a pixelof a known lateral electric field mode liquid crystal device.

DETAILED DESCRIPTION

Embodiments of the present application will be described below in detailwith reference to the drawings.

First Embodiment

A liquid crystal device according to a first embodiment of the inventionwill be described herein below with reference to FIGS. 1 to 4. Theliquid crystal device according to this embodiment is an example of aFFS mode color liquid crystal display device. FIG. 1 is an equivalentcircuit diagram of the liquid crystal device according to thisembodiment. FIG. 2 is a plan view illustrating a configuration of onepixel of the liquid crystal device. FIG. 3 is a cross-sectional viewillustrating the configuration of one pixel of the liquid crystaldevice. In the drawings below, individual members are appropriatelydepicted with different reduced scales in order to make them largeenough to be recognized on the drawings.

A liquid crystal device 1 according to this embodiment is a color liquidcrystal display device in which one pixel is configured by threesub-pixels capable of outputting color light of red (R), green (G) andblue (B). Here, a display region which serves the minimum unit ofdisplay will be referred to as “sub-pixel,” and a display regioncomposed of a group (R, G and B) of sub-pixels will be referred to as“pixel.” Further, in this specification, “a long-axis direction of thesub-pixel” corresponds to the Y-axis direction in FIG. 2. That is, “thelong-axis direction of the sub-pixel” is defined not as a directionextending along an extending direction of bent portions oflater-described pixel electrodes, but as a direction in which sub-pixelsof the same color are arranged. Moreover, “a short-axis direction of thesub-pixel” corresponds to the X-axis direction perpendicular to theY-axis direction in FIG. 2.

As illustrated in FIG. 1, in the liquid crystal device 1 according tothis embodiment, pixel electrodes (second electrodes) 11 are provided tocorrespond to respective one of a plurality of sub-pixels 2R, 2G and 2B(see FIG. 2) which is arranged in a matrix to form a display region.Moreover, the pixel electrodes 11 are connected to pixel switching TFT(Thin Film Transistor) elements 12 for controlling the conduction stateof the corresponding pixel electrodes 11. Data lines 13 are electricallyconnected to respective sources of the TFT elements 12. Image signalsS1, S2, . . . , and Sn are supplied from a data line driving circuit 16to the respective data lines 13. It is to be noted that capacitancelines 20 are not always necessary and may be provided as necessary.

Moreover, scan lines 14 are electrically connected to respective gatesof the TFT elements 12. Scan signals G1, G2, . . . , and Gm are suppliedin a pulsating manner at a predetermined timing from a scan line drivingcircuit 17 to the respective scan lines 14. The scan signals G1, G2, andGm are applied in this order to the respective scan lines 14 in aline-sequential manner. Further, the pixel electrodes 11 areelectrically connected to respective drains of the TFT elements 12. Whenthe TFT elements 12 which are switching elements are turned on for onlya predetermined period by the scan signals G1, G2, . . . , and Gmsupplied from the scan lines 14, the image signals S1, S2, . . . , andSn supplied from the data lines 13 are written to liquid crystals ofrespective pixels at a predetermined timing.

The image signals S1, S2, . . . , and Sn having a predetermined levelhaving written to the liquid crystals are held for a predeterminedperiod by liquid crystal capacitances formed between the pixelelectrodes 11 and later-described common electrodes (first electrodes).Further, in order to prevent the held image signals S1, S2, . . . , andSn from leaking, storage capacitances 18 are formed between the pixelelectrodes 11 and the capacitance lines 20 so as to be parallel with theliquid crystal capacitances. When voltage signals are applied to theliquid crystals, the alignment state of the liquid crystal molecules ischanged in accordance with the applied voltage level. In this way, lightincident on the liquid crystals is modulated to perform gradationdisplay.

Next, the configuration of the pixel of the liquid crystal device 1according to this embodiment will be described. FIG. 2 is a plan viewillustrating a pattern configuration of one pixel composed of threesub-pixels 2R, 2G and 2B of three colors R, G and B. As illustrated inFIG. 2, the pixel electrode 11 provided to each of the sub-pixels 2R, 2Gand 2B has such a rectangular shape that is bent at the center in along-axis direction thereof. Specifically, both sides of a bent portionK are bent to be inclined in opposite directions with respect to thelong-axis direction of the sub-pixels 2R, 2G and 2B so that an upperhalf part thereof is inclined toward the top left corner in FIG. 2 whilea lower half part thereof is inclined toward the bottom left corner.

Moreover, inside the pixel electrode 11, a plurality of slits (gaps) 3is formed so as to extend in the same direction as an extendingdirection of an outer border 11 a of the pixel electrode 11. That is,the slits 3 are bent so that both sides of the bent portion K areinclined in opposite directions with respect to the long-axis directionof the sub-pixels 2R, 2G and 2B in a manner similar to the sub-pixels2R, 2G and 2B in which the upper half parts thereof are inclined towardthe top left corner in FIG. 2 while the lower half parts thereof areinclined toward the bottom left corner. Although only four slits 3 areillustrated in FIG. 2 in order to make them large enough to berecognized on the drawings, many more slits may be formed in practicalcases. As a result, linear electrodes 4 are formed by both sides of theslits 3.

In the case of this embodiment, a region disposed between bent portionsK of two linear electrodes 4 adjacent in the short-axis direction of thesub-pixels 2R, 2G and 2B corresponds to the slit 3. That is, the slits 3are formed between bent portions K of two adjacent linear electrodes 4,and the slits 3 are connected with each other across both sides of thebent portions K in the long-axis direction of the sub-pixels 2R, 2G and2B. Further, in this embodiment, the width L of the linear electrodes 4and the width S of the slits 3 are constant within the pixel electrode11.

The TFT element 12 is provided at the top right corner of each of thesub-pixels 2R, 2G and 2B in FIG. 2. The TFT element 12 includes a gateelectrode 22 formed to be integral with the scan line 14, asemiconductor layer 23, a source electrode 24 formed to be integral withthe data line 13, and a drain electrode 25. Here, reference numeral 26is a contact hole for electrically connecting the drain electrode 25 andthe pixel electrode 11 to each other. The data line 13 is formed to bebent along the same direction as the extending direction of the linearelectrode 4 having the bent portion K. In the case of this embodiment,since the extending direction of the linear electrode 4 is identicalwith the extending direction of the outer border 11 a of the pixelelectrode 11, the configuration can be restated as follows: the dataline 13 is formed to be bent along the extending direction of the outerborder 11 a of the pixel electrode 11 with a predetermined gap from theouter border 11 a of the pixel electrode 11. It is to be noted that thepixel electrode 11 may be bent so that both sides of the bent portion Kare inclined in opposite direction to the long-axis direction of thesub-pixels 2R, 2G and 2B in a manner that the upper half part thereof isinclined toward the top right corner while the lower half part thereofis inclined toward the bottom right corner. Although it is preferablethat the inclination angles are equal to each other, the inclinationangles may be different from each other.

Next, a cross-sectional structure of the liquid crystal device 1according to this embodiment will be described. As illustrated in FIG.3, the liquid crystal device 1 includes an element substrate (firstsubstrate) 28, a counter substrate (second substrate) 29 that isdisposed to face the element substrate 28, a liquid crystal layer 30that is sandwiched between the element substrate 28 and the countersubstrate 29, a polarization plate 31 that is provided on an outersurface side (a side opposite the liquid crystal layer 30) of theelement substrate 28, and a polarization plate 32 that is provided anouter surface side of the counter substrate 29. The liquid crystaldevice 1 is configured such that an illumination light is irradiatedthereto from a backlight (not illustrated) disposed on the outer surfaceside of the element substrate 28. Further, in the liquid crystal device1, sealing members (not illustrated) are provided along thecircumferences of opposite surfaces of the element substrate 28 and thecounter substrate 29, and the liquid crystal layer 30 is sealed within aspace surrounded by the sealing members, the element substrate 28 andthe counter substrate 29.

The element substrate 28 includes a substrate body 33 formed of atransparent material such as glass, quartz or plastic, and a gateinsulating film 34, an interlayer insulating film 35 and an alignmentfilm 36 for controlling an initial alignment direction (rubbingdirection) of the liquid crystal layer 30, which are stacked in thisorder on a surface on an inner side (a side close to the liquid crystallayer 30) of the substrate body 33.

The element substrate 28 is provided with the gate electrode 22 (scanline 14) disposed on the inner surface of the substrate body 33, thecommon electrodes (first electrodes) 37 provided so as to correspond toeach of the sub-pixels, common lines 38 configured to connect the commonelectrodes 37 with each other, the data line 13 (see FIG. 2) disposed onthe inner surface of the gate insulating film 34, the semiconductorlayer 23, the source electrode 24, the drain electrode 25, and the pixelelectrode 11 disposed on the inner surface of the interlayer insulatingfilm 35. The gate insulating film 34 is formed of a transparent materialhaving insulating properties such as a silicon nitride or a siliconoxide so as to cover the scan lines 14, the common lines 38 and thecommon electrodes 37 formed on the substrate body 33.

The interlayer insulating film 35 is formed of a transparent materialhaving insulating properties such as a silicon nitride or a siliconoxide, similar to the gate insulating film 34 so as to cover thesemiconductor layer 23, the source electrodes 24 and the drain electrode25 formed on the gate insulating film 34. Further, contact holes 26which are through-holes for achieving conduction between the pixelelectrodes 11 and the TFT elements 12 are formed at portion of theinterlayer insulating film 35 where the drain electrodes 25 and thepixel electrodes 11 overlap with each other in plan view illustrated inFIG. 2. The alignment film 36 is formed of an organic material such aspolyimide so as to cover the pixel electrodes 11 on the interlayerinsulating film 35. Further, an alignment treatment for controlling thealignment of the liquid crystal molecules constituting the liquidcrystal layer 30 is performed to the upper surface of the alignment film36.

The counter substrate 29 includes a substrate body 40 formed of atransparent material such as glass, quartz or plastic, and coloredlayers 41 of color filters and an alignment film 42 which are stacked inthis order on a surface on an inside (a side close to the liquid crystallayer 30) of the substrate body 40. The colored layers 41 are disposedso as to correspond to the sub-pixels 2R, 2G and 2B, are formed ofacryl, for example, and contain coloring materials corresponding tocolors to be displayed by the sub-pixels 2R, 2G and 2B. The alignmentfilm 42 is formed of an organic material such as polyimide or aninorganic material such as a silicon oxide similar to the alignment film36 and has an alignment direction thereof identical with an alignmentdirection of the alignment film 36.

Polarization plates 31 and 32 provided on outer surfaces of therespective substrates have transmission axes thereof being perpendicularto each other. Therefore, a transmission axis of one of the polarizationplates is parallel with the alignment direction of the alignment film 36while a transmission axis of the other polarization plate isperpendicular to the alignment direction of the alignment film 36.

In the liquid crystal device 1 according to this embodiment, since bothsides (the upper and lower sides in FIG. 2) of the bent portion K ofeach of the linear electrodes 4 constituting the pixel electrode 11 havesuch a shape that is inclined in opposite directions, two domains areformed within one sub-pixel 2R, 2G or 2B, whereby it is possible toachieve a wide viewing angle. Moreover, since the linear electrodes 4(or the slits 3) extend in the long-axis direction of the sub-pixels 2R,2G and 2B, the respective parts of the linear electrodes 4 (or the slits3) extend in a direction parallel with the outer border 11 a of thepixel electrode 11, and the data line 13 is bent along the extendingdirection of the outer border 11 a of the pixel electrode 11, it ispossible to suppress generation of spaces, which do not contribute todisplay, at positions along the longer sides of the pixel electrode 11,thereby increasing the aperture ratio compared with the known example.Furthermore, in the case of this embodiment, since the slits 3 areconnected with each other across both sides of the bent portions K, itis possible to further increase the aperture ratio. In this way, aliquid crystal device having a high display luminance can be provided.In addition, the sub-pixel is long in the extending direction of thedata line 13. That is, the extending direction of the data line 13corresponds to the long-axis direction of the sub-pixel. However, thesub-pixel may be long in the extending direction of the scan line 14.That is, when the extending direction of the scan line 14 corresponds tothe long-axis direction of the sub-pixel, the linear electrodes areformed along the extending direction of the scan line 14.

Second Embodiment

A liquid crystal device according to a second embodiment of theinvention will be described herein below with reference to FIG. 4. Abasic configuration of the liquid crystal device according to thisembodiment is the same as that of the first embodiment, except that thepixel electrode is configured differently from that of the firstembodiment. FIG. 4 is a plan view illustrating the configuration of onepixel of the liquid crystal device according to this embodiment. In FIG.4, the same constituent elements as those of FIG. 2 used in the firstembodiment will be denoted by the same reference numerals and thedetailed descriptions thereof will be omitted.

In the first embodiment, the slits 3 formed within the pixel electrode11 were formed to be connected with each other across both sides of thebent portions K. To the contrary, in the liquid crystal device accordingto this embodiment, as illustrated in FIG. 4, connection portions 55 areformed between the bent portions K of two linear electrodes 54 adjacentin the short-axis direction of the sub-pixels 2R, 2G and 2B so as toconnect the two adjacent linear electrodes 54 with each other. That is,slits 53 are individually formed on both sides of the bent portions Kand the slits 53 on both sides of the bent portions K are divided by theconnection portions 55.

In the liquid crystal device according to this embodiment, it ispossible to obtain the same advantage as the first embodiment that it ispossible to provide a liquid crystal device capable of achieving a wideviewing angle, a high aperture ratio, and a high display luminance. Ifthe slits 3 are connected with each other across both sides of the bentportions K as in the case of the first embodiment, there is a fear thatit may cause problems that display defects resulting from an alignmentdisorder (disclination) of liquid crystals at the bent portions K mayspread beyond expectation or that the display defects may be unstablytransferred to other positions upon application of an external force tothe liquid crystal device. To the contrary, according to the liquidcrystal device of this embodiment, it is possible to solve the problemsby dividing the slits 53 on both sides of the bent portions K by theconnection portions 55.

Third Embodiment

A liquid crystal device according to a third embodiment of the inventionwill be described herein below with reference to FIG. 5. A basicconfiguration of the liquid crystal device according to this embodimentis the same as that of the first and second embodiments, except that thepixel electrode is configured differently from that of the first andsecond embodiments. FIG. 5 is a plan view illustrating the configurationof one pixel of the liquid crystal device according to this embodiment.In FIG. 5, the same constituent elements as those of FIG. 2 used in thefirst embodiment will be denoted by the same reference numerals and thedetailed descriptions thereof will be omitted.

In the first and second embodiments, the width L of the linearelectrodes and the width S of the slits were constant within the pixelelectrode. To the contrary, in the liquid crystal device according tothis embodiment, as illustrated in FIG. 5, the width of the linearelectrodes and the width of the slits are configured such that the widthL1 of the linear electrode and the width S1 of the slit disposed at aregion located in the vicinity of the circumference of the sub-pixel andclose to the data line are relatively large while the width L2 of thelinear electrode and the width S2 of the slit disposed at a regionlocated in the vicinity of the center of the sub-pixel and distant fromthe data line are relatively small.

Further, although in this embodiment, both the width L of the linearelectrodes and the width S of the slits are changed, only either one ofthem may be changed. Specifically, while maintaining the constant widthof the linear electrodes within the pixel electrode, the width S1 of theslit disposed at a region located in the vicinity of the circumferenceof the sub-pixel and close to the data line may be relatively large, andthe width S2 of the slit disposed at a region located in the vicinity ofthe center of the sub-pixel and distant from the data line may berelatively small. Alternatively, while maintaining the constant width ofthe slits within the pixel electrode, the width L1 of the linearelectrode disposed at a region located in the vicinity of thecircumference of the sub-pixel and close to the data line may berelatively large, and the width L2 of the linear electrode disposed at aregion located in the vicinity of the center of the sub-pixel anddistant from the data line may be relatively small.

In the liquid crystal device according to this embodiment, it ispossible to obtain the same advantage as the first and secondembodiments that it is possible to provide a liquid crystal devicecapable of achieving a wide viewing angle, a high aperture ratio, and ahigh display luminance.

Since the invention is characterized in that the data line is bent so asto extend along the outer border of the pixel electrode, although it ispossible to provide a high aperture ratio, there is a fear that when alarger part of the outer border of the pixel electrode is located inclose proximity of the data line, a crosstalk may occur between the dataline and the pixel electrode, thus leading to display defects.Therefore, as in the case of this embodiment, when the width L1 and S1of the linear electrode 54 and the slit 53 disposed at the regionlocated in the vicinity of the circumference of the sub-pixel and closeto the data line 13 are larger than the width L2 and S2 of the linearelectrode 54 and the slit 53 disposed at the region located in thevicinity of the center of the sub-pixel and distant from the data line13, it is possible to make the potential of the pixel electrode 51 lesslikely to be influenced by the data line 13 to thereby suppress theoccurrence of the crosstalk.

Fourth Embodiment

A liquid crystal device according to a fourth embodiment of theinvention will be described herein below with reference to FIGS. 6 to 8.A basic configuration of the liquid crystal device according to thisembodiment is the same as that of the first to third embodiments, exceptthat the positional relationship of the electrodes is different fromthat of the first to third embodiments. FIG. 6 is a plan viewillustrating the configuration of one pixel of the liquid crystal deviceaccording to this embodiment. FIG. 7 is a cross-sectional viewillustrating the configuration of one pixel of the liquid crystaldevice. FIG. 8 is a diagram illustrating the arrangement of optical axesof the liquid crystal device. In the drawings below, individual membersare appropriately depicted with different reduced scales in order tomake them large enough to be recognized on the drawings. Moreover, thesame constituent elements as those of the first to third embodimentswill be denoted by the same reference numerals and the detaileddescriptions thereof will be omitted.

In the first to third embodiments, the common electrode was provided ona lower surface side (substrate body side) of the element substrate, andthe pixel electrode was provided on an upper layer side (liquid crystallayer side) of the element substrate. To the contrary, in the liquidcrystal device according to this embodiment, as illustrated in FIG. 7, apixel electrode (first electrode) 61 is provided on a lower surface side(a side close to the substrate body 33) of an element substrate (firstsubstrate) 68, and common electrode (second electrode) 67 are providedon an upper layer side (a side close to the liquid crystal layer 30) ofthe element substrate 68. Therefore, as illustrated in FIG. 6, thecommon electrode 67 includes linear electrodes 64 and slits 63.

More specifically, in the liquid crystal device 1A, as illustrated inFIG. 7, the liquid crystal layer 30 is sandwiched between the elementsubstrate 68 and the counter substrate 69. Although not illustrated, thethickness of the liquid crystal layer 30 is maintained constant by aspacer. A polarization plate 31 is formed on an outer surface of theelement substrate 68, and a polarization plate 32 is formed on an outersurface of the counter substrate 69. Further, a backlight 74 is arrangedso as to irradiate light toward the outer surface side of the elementsubstrate 68.

First, a configuration of the element substrate 68 will be described.The element substrate 68 has a substrate body 33 as its base. On asurface of the substrate body 33 of the element substrate 68 close tothe liquid crystal layer 30, scan lines 14 which are branched from thegate electrodes 22 are formed so as to extend in the X-axis direction inFIG. 6, and a gate insulating film 34 is formed so as to cover the gateelectrodes 22 and the scan lines 14. A semiconductor layer 23 is formedon the gate insulating film 34 so as to face the gate electrodes 22, anda source electrode 24 and a drain electrode 25 are formed so as topartially cover the semiconductor layer 23. In this way, TFT elements 12are formed by the semiconductor layer 23, the gate electrodes 22, thesource electrodes 24 and the drain electrodes 25. The source electrodes24 are branched from the data lines 13, and the data electrodes 13extend in the Y-axis direction in FIG. 6.

A passivation film 76 formed of a silicon oxide or a silicon nitride soas to cover the semiconductor layer 23, the source electrodes 24 and thedrain electrodes 25, and a first interlayer insulating film 71 is formedso as to cover the passivation film 76. Moreover, pixel electrodes 61formed of a transparent conductive material are formed individually foreach sub-pixel so as to cover the first interlayer insulating film 71.Contact holes 26 are formed to penetrate through the passivation film 76and the first interlayer insulating film 71 and reach the drainelectrodes 25 so that the pixel electrodes 61 and the drain electrodes25 are electrically connected to each other via the contact holes 26.

A second interlayer insulating film 72 is formed so as to cover thepixel electrodes 61. Common electrodes 67 formed of a transparentconductive material are formed on a surface of the second interlayerinsulating film 72 close to the liquid crystal layer 30. The commonelectrode 67 is formed over the entire sub-pixels and acts as a counterelectrode. The common electrode 67 includes linear electrodes 64 formedby a plurality of slits 63 extending approximately in the Y-axisdirection in FIG. 6. The slits 63 are formed by etching the commonelectrode 67 by means of a photolithographic method. A storagecapacitance is formed between the pixel electrode 61 and the commonelectrode 67 with the second interlayer insulating film 72 sandwichedbetween the pixel electrode 61 and the common electrode 67 being used asa dielectric film. Further, an alignment film 36 is formed so as tocover the common electrode 67 and the second interlayer insulating film72. A rubbing treatment is performed to the alignment film 36 in apredetermined direction.

Next, a configuration of the counter substrate 69 will be described. Thecounter substrate 69 has a substrate body 40 as its base, and coloredlayers 41 of color filters capable of passing therethrough differentcolor light (for example, R, G, B, white, and the like) for eachsub-pixel and a black matrix (light shielding film) 73 as a lightshielding member are formed on the substrate body 40. A protective resinlayer 78 is formed so as to cover the colored layers 41 and the blackmatrix 73, and an alignment film 42 is formed so as to cover theprotective resin layer 78. A rubbing treatment is performed to thealignment film 42 in a direction opposite to that of the alignment film36.

Here, the arrangement of the optical axes will be described. Asillustrated in FIG. 8, a transmission axis 31 a of the polarizationplate 31 on the element substrate 68 and a transmission axis 32 a of thepolarization plate 32 on the counter substrate 69 are arranged so as tobe perpendicular to each other, and the transmission axis 32 a of thepolarization plate 32 is arranged to be parallel with the Y-axisdirection in FIG. 6. Moreover, the rubbing direction of the alignmentfilm 36 is parallel with the transmission axis 32 a of the polarizationplate 32. Further, the rubbing direction of the alignment film 36intersects the principal direction of an electric field generatedbetween the common electrode 67 and the pixel electrode 61. In addition,the liquid crystal molecules which were parallelly aligned along therubbing direction in an initial state are rotated to be aligned towardthe principal direction of the electric field in response to applicationof an electric voltage between the common electrode 67 and the pixelelectrode 61. Based on a difference between the initial alignment stateand the alignment state during voltage application, brightness isrepresented for each of the sub-pixels. In this way, the sub-pixels aredriven to display images. Although not illustrated, the liquid crystallayer 30 is sealed within a sealing area formed by sealing memberprovided between the element substrate 68 and the counter substrate 69.The slits 63 extend in the vertical direction (Y-axis direction in FIG.6).

Here, the rotation direction of the liquid crystals of the liquidcrystal layer 30 in the slits 63 will be described. The electric fieldapplied to the liquid crystal layer 30 is generated by a potentialdifference between the common electrode 67 and the pixel electrode 61located in the slits 63. The electric field is generated approximatelyin parallel with the plane of the element substrate 68, and thedirection of the electric field in plan view corresponds to a normaldirection of the sides of the slits 63. When there is no potentialdifference between the common electrode 67 and the pixel electrode 61,that is, when the electric field is in an OFF state, the alignmentdirection of the liquid crystals corresponds to the rubbing direction.When the electric field is in an ON state, the alignment direction ofthe liquid crystals corresponds to the normal direction of the sides ofthe slits 63. When the electric field changes from the OFF state to theON state, the liquid crystals rotate in a direction where a rotationangle thereof is small. Therefore, when the potential difference betweenthe common electrode 67 and the pixel electrode 61 changes from an OFFstate to an ON state, the liquid crystals on the lower half part rotatein the counter-clockwise direction and the liquid crystals on the upperhalf part rotate in the clockwise direction.

Since the color sub-pixel is vertically long, when the slits 63 arearranged to extend in the horizontal direction, the number of both endsof the slits 63 may increase. Therefore, in the liquid crystal device 1Aaccording to this embodiment, as illustrated in FIG. 6, the extendingdirection of the slits 63 corresponds to the vertical direction (Y-axisdirection) so that the number of end portions of the slits 63 isdecreased, and thus, a decrease in the aperture ratio is suppressed.

If the entire slits 63 are inclined in the clockwise direction or thecounter-clockwise direction, the liquid crystal molecules may be twistedin one direction, and thus, a phenomenon that images are displayed indifferent colors depending on viewing directions may occur. This isbecause a visual retardation changes depending on directions whereliquid crystal molecules are observed. In order to suppress such aproblem, in the liquid crystal device 1A according to this embodiment,there are provided a domain where the extending direction of the slits63 is inclined in the clockwise direction at an angle range of +3 to +10degree with respect to the Y axis and a domain having an inclinationangle range of −3 to −10 degree. That is, a multi-domain structure inwhich the linear electrodes 64 have a chevron shape is realized. Forexample, as illustrated in FIG. 8, a domain where the extendingdirection L of the lower half part of the slit 63 is inclined in theclockwise direction at an angle of +5 degree with respect to the Y axisand a domain where the extending direction H of the upper half partthereof is inclined at an angle of −5 degree, whereby a multi-domainstructure is realized. Although in the liquid crystal device 1Aaccording to this embodiment, the number of domains having differentalignment directions is two, many more domains having differentalignment directions may be provided. In addition, the invention is notlimited to the case where the extending direction of the lower half partof the slit 63 is inclined at the angle of +5 degree, but the lower halfpart of the slit may be formed by connecting a portion extending at aninclination angle of +10 degree and a portion extending at aninclination angle of +5 degree with each other. In such a case,similarly, as for the extending direction of the upper half part of theslit 63, the upper half part of the slit may be formed by connecting aportion extending at an inclination angle of −10 degree and a portionextending at an inclination angle of −5 degree. Moreover, in such acase, the data line 13 may be shaped to be inclined along the slit 63.

Next, the relationship between the slits 63 of the common electrode 67and the black matrix 73 will be described. The common electrode 67 isformed across the entire sub-pixels, and portions that are not hatchedin FIG. 6 are the slits 63 of the common electrode 67. The shadedportion is the black matrix 73. As illustrated in FIGS. 6 and 7, thecommon electrode 67 overlaps with the black matrix 73 as viewed in planview, and the slits 63 are formed so as not to overlap with the blackmatrix 73 as viewed in plan view.

Moreover, the black matrix 73 and the data lines 13 are arranged toextend in parallel with the slits 63. Therefore, it is possible todecrease the regions which do not contribute to display compared with aliquid crystal device having data lines extending in parallel with the Yaxis, thereby increasing the aperture ratio.

Modification

A liquid crystal device according to a modification will be describedherein below with reference to FIG. 9. A basic configuration of theliquid crystal device according to this modification is the same as thatof the first to third embodiments, except that the positionalrelationship of the electrodes is different from that of the first tothird embodiments. FIG. 9 is a cross-sectional view of the liquidcrystal device according to the modification. In FIG. 9, the sameconstituent elements as those of FIG. 3 used in the first embodimentwill be denoted by the same reference numerals and the detaileddescriptions thereof will be omitted.

In the first to third embodiments, the common electrode was provided ona lower surface side (substrate body side) of the element substrate, andthe pixel electrode was provided on an upper layer side (liquid crystallayer side) of the element substrate. To the contrary, in the liquidcrystal device according to this modification, as illustrated in FIG. 9,a pixel electrode (first electrode) 61 is provided on a lower surfaceside (a side close to the substrate body 33) of an element substrate(first substrate) 68, and common electrode (second electrode) 67 areprovided on an upper layer side (a side close to the liquid crystallayer 30) of the element substrate 68. Therefore, the common electrode67 includes linear electrodes 64 and slits 63.

More specifically, the first interlayer insulating film 71 is formed soas to cover the TFT element 12, and a beta-shaped pixel electrode 61 isformed on the first interlayer insulating film 71. The pixel electrode61 and the drain electrode 25 are electrically connected to each othervia the contact hole 26 penetrating through the first interlayerinsulating film 71. The second interlayer insulating film 72 is formedso as to cover the pixel electrode 61, and the common electrode 67having a plurality of linear electrodes 64 is formed on the secondinterlayer insulating film 72. The alignment film 36 is formed so as tocover the common electrode 67. Moreover, a black matrix 73 is formed onthe first interlayer insulating film 71 so as to cover the data lines13, the scan lines 14, the TFT elements 12, and the like.

In addition, when the common electrode 67 is used as the secondelectrode as in the case of this modification, rather than providing thecommon electrode 67 formed on the second interlayer insulating film 72to be divided for each of the sub-pixels, a configuration may be used inwhich the common electrode 67 is formed over the entire display regionsof the liquid crystal display device, and in which the linear electrodes64 and the slits 63 are formed for each of the sub-pixels.

In the liquid crystal device according to this modification, it ispossible to obtain the same advantage as the first to third embodimentsthat it is possible to provide a liquid crystal device capable ofachieving a wide viewing angle, a high aperture ratio, and a highdisplay luminance.

Moreover, in accordance with the invention, the data lines are bent soas to comply with the shape of the electrode having the linearelectrodes, whereby the dead spaces which do not contribute to displayare reduced in the regions disposed along the data lines, and thus, theaperture ratio is increased. However, in the case where the black matrixis formed on the counter substrate side, the positional alignmentaccuracy between the data lines and the black matrix is not high enoughbecause the accuracy depends on the bonding accuracy of the twosubstrates. As a result, the thus-obtained advantage of an improvementin the aperture ratio may fade away.

To the contrary, according to the configuration of this modification,since the data lines 13 and the black matrix 73 are formed on theelement substrate 68, unlike a case where the data lines and the blackmatrix are formed on different substrates, the positional alignmentaccuracy between the data lines 13 and the black matrix 73 may depend onthe alignment accuracy of the photographic process, which is much higherthan the bonding accuracy of the substrates. Therefore, the positionalalignment between the data lines 13 and the black matrix 73 can beperformed with a high accuracy, and thus, a high aperture ratio can bemaintained. Electronic Apparatus

Next, an electronic apparatus having the above-described liquid crystaldevice will be described. FIG. 10 is a perspective view of a cellularphone as an example of the electronic apparatus having the liquidcrystal device according to the invention. As illustrated in FIG. 10,the cellular phone 300 includes a body portion 301 and a display portion302 configured to be opened and closed with respect to the body portion301. A display 303 is disposed in an inner portion of the displayportion 302, and various icons, characters and images related to phonecalls are displayed on a display screen 304. Moreover, manipulationbuttons 305 are arranged on the body portion 301.

Further, an antenna 306 is attached to one end portion of the displayportion 302 to be freely extended and contracted. A speaker (notillustrated) is installed inside an earpiece part 307 that is providedon an upper portion of the display portion 302. Further, a microphone(not illustrated) is installed inside a mouthpiece part 308 that isprovided on the lower end portion of the body portion 301. Here, theliquid crystal device according to the above embodiment is used as thedisplay 303.

In accordance with the cellular phone of this embodiment, since thecellular phone is provided with the liquid crystal device according tothe above-described embodiment, it is possible to realize a cellularphone having a liquid crystal display unit capable of achieving a highdisplay luminance and a wide viewing angle.

The electronic apparatus having the liquid crystal device is not limitedto the cellular phone but other electronic apparatuses may be used suchas a personal computer, a notebook type personal computer, aworkstation, a digital camera, a vehicle-mounted monitor, a carnavigation apparatus, a head-mounted display, a digital video camera, atelevision receiver, a view-finder type or monitor-direct-view typevideo tape recorder, a pager, a electronic note, an electroniccalculator, an electronic book, a projector, a word processor, a videophone, a POS terminal, or an apparatus equipped with a touch panel.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The application is claimed as follows:
 1. A liquid crystal device,comprising: a first substrate and a second substrate that are disposedto face each other; a liquid crystal layer that is sandwiched betweenthe first substrate and the second substrate; a first electrode that isprovided on the liquid crystal layer side of the first substrate; aninsulating layer that is provided on the liquid crystal layer side ofthe first electrode; and a second electrode that is provided on theliquid crystal layer side of the insulating layer, wherein: the firstsubstrate has formed thereon a plurality of data lines and a pluralityof scan lines which intersect each other; sub-pixels are formed atregions surrounded by the data lines and the scan lines; the secondelectrode has a plurality of linear electrodes that is disposed with agap therebetween; each of the plurality of linear electrodes extends ina long-axis direction of the sub-pixels and has at least one bentportion; the bent portion has such a shape that both sides thereof areinclined in opposite directions with respect to the long-axis directionof the sub-pixels; and the data lines or the scan lines are bent in anextending direction of the linear electrodes having the bent portion. 2.The liquid crystal device according to claim 1, wherein the firstelectrode is a pixel electrode, and wherein the second electrode is acommon electrode.
 3. The liquid crystal device according to claim 1,wherein each of the plurality of linear electrodes is linearly symmetricabout a short-axis direction of the bent portion.
 4. The liquid crystaldevice according to claim 1, wherein a region disposed between bentportions of two linear electrodes adjacent in a short-axis direction ofthe sub-pixels is a gap between the two adjacent linear electrodes. 5.The liquid crystal device according to claim 1, wherein a connectionportion is provided to a region disposed between bent portions of twoadjacent linear electrodes in a short-axis direction of the sub-pixelsso as to connect the two adjacent linear electrodes with each other. 6.The liquid crystal device according to claim 1, wherein among theplurality of linear electrodes and the gaps alternately arranged in ashort-axis direction of the sub-pixels, the linear electrode and the gapdisposed at a region located close to the bent data line or the bentscan line has a width larger than a width of the linear electrode andthe gap disposed at a region located distant from the bent data line orthe bent scan line.
 7. The liquid crystal device according to claim 1,wherein among the linear electrodes arranged in a short-axis directionof the sub-pixels, the linear electrode disposed at a region locatedclose to the bent data line or the bent scan line has a width largerthan a width of the linear electrode disposed at a region locateddistant from the bent data line or the bent scan line.
 8. The liquidcrystal device according to claim 1, wherein among a plurality of thegaps arranged in a short-axis direction of the sub-pixels, the gapdisposed at a region located close to the bent data line or the bentscan line has a width larger than a width of the gap disposed at aregion located distant from the bent data line or the bent scan line. 9.The liquid crystal device according to claim 1, further comprising alight shielding film configured to overlap with the data line or thescan line which is at least bent in plan view, the light shielding filmbeing provided on the first substrate.
 10. The liquid crystal deviceaccording to claim 1, further comprising a light shielding filmconfigured to overlap with the data line or the scan line which is atleast bent in plan view, the light shielding film being provided on thesecond substrate.